1. Field of the Invention
The present invention relates to a head-up display device for a moving body, such as an automobile or the like, and more particularly, to a head-up display device for a large vehicle.
2. Description of the Related Art
In the past, a head-up display device has been known as a device that displays information, such as the indication of a direction, calling for attention, and a travel speed, to a driver of an automobile or the like. The head-up display device is to project the virtual image of an image, which is to be displayed, to the reflective optical surface of a front window, a combiner, or the like so that a driver can recognize information required for the driving of an automobile or the like without taking his eyes off from the field of view. JP2013-61554A is proposed as such a head-up display device. JP2013-61554A discloses a head-up display device in which an image forming unit mounted on a vehicle, such as a passenger car, is disposed in front of a driver so that the driver can visually recognize an enlarged virtual image of a two-dimensional image formed on an image display surface by a first mirror, a second mirror, and a reflective optical surface.